Herbal Nanobiotechnology Lab, Pharmacology Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India.
Sci Rep. 2019 Apr 24;9(1):6520. doi: 10.1038/s41598-019-43016-w.
The indiscriminate use of antibiotics has led to the emergence of drug-resistant bacteria which has become one of the biggest challenges of the twenty-first century for the researchers to combat and in turn search for novel targets which could lead to the development of effective and sustainable therapies. Inhibition of biofilm formation and virulence of bacterial pathogens is an emerging approach to address the challenges related to bacterial infections. To suppress the virulence and biofilm formation by Escherichia coli O157:H7 (ECOH), we developed stable nanoemulsion (NE) of Gaultheria fragrantissima Wall. essential oil's (EO) bioactive compounds, viz., eugenol (E-NE) and methyl salicylate (MS-NE) that showed significantly higher anti-biofilm and anti-virulence activities as compared to eugenol and methyl salicylate without affecting ECOH planktonic cell growth. Transcriptional analysis showed that E-NE and MS-NE reduced the expression of genes, including curli, type I fimbriae, Shiga-like toxins, quorum sensing, and ler-controlled toxins, which are needed for biofilm formation, pathogenicity, and attachment. E-NE and MS-NE loaded hydrogel coatings showed superior anti-biofilm activity against ECOH on glass, plastic and meat surfaces as compared to eugenol and methyl salicylate loaded coatings. Conclusively, NE-loaded hydrogel coatings could be used in combating ECOH infection on solid surfaces through anti-biofilm and anti-virulence strategies.
抗生素的滥用导致了耐药菌的出现，这已成为 21 世纪研究人员面临的最大挑战之一，他们需要寻找新的靶点，从而开发出有效且可持续的治疗方法。抑制生物膜的形成和细菌病原体的毒力是解决与细菌感染相关挑战的一种新兴方法。为了抑制大肠杆菌 O157:H7（ECOH）的毒力和生物膜形成，我们开发了含有高良姜挥发油生物活性化合物（例如丁香酚和水杨酸甲酯）的稳定纳米乳液（NE），与丁香酚和水杨酸甲酯相比，E-NE 和 MS-NE 具有更高的抗生物膜和抗毒力活性，而不会影响 ECOH 浮游细胞的生长。转录分析表明，E-NE 和 MS-NE 降低了生物膜形成、致病性和附着所需的基因表达，包括卷曲蛋白、I 型菌毛、志贺样毒素、群体感应和 ler 控制的毒素。与丁香酚和水杨酸甲酯负载的水凝胶涂层相比，负载 E-NE 和 MS-NE 的水凝胶涂层在玻璃、塑料和肉表面上对 ECOH 的抗生物膜活性更高。总之，负载 NE 的水凝胶涂层可通过抗生物膜和抗毒力策略用于对抗固体表面上的 ECOH 感染。
